1. Field of the Invention
The invention relates to a method of sealing apertures between two environments such that the seal may be removed remotely and completely. More specifically, the invention relates to a method of sealing apertures between two environments with a fully consumable material which may be ignited remotely leaving clear passage between the environments without damage to either environment.
2. Description of Prior Art
Frequently it is desirable to protectively seal an aperture or open duct or the like between two environments and at a later time remotely remove the seal without degrading the region protectively sealed. Such seals find extensive use in aerospace applications for sealing out weather, corrosive chemicals, vacuums and the like. Where such a seal is used as a protective interface between two regions, it must be lightweight, reliable and capable of resisting potentially high pressure and temperature differentials across the interface. Currently, there are three techniques primarily practiced by prior art.
One technique is to use motor-driven or solenoid-operated valves or metal shades to seal the aperture. However, the valve and associated motor are typically heavy (generally an order of magnitude heavier than the present invention) and bulky as well as susceptible to malfunction in low-temperature applications. Another technique is to use frangible diaphragms in which the sealing diaphragm is either punctured or caused to explode. The former technique typically results in the aperture still being partially occluded and flow across the interface somewhat inhibited. The latter technique typically uses an explosive charge laminated between two or more frangible layers and when the charge is ignited the seal is blown away. However, personnel, sensitive equipment and surfaces either side of the seal may be damaged by the explosive shock wave or by seal fragments having velocity as high as 2000 ft/sec. A last technique within prior art is the fabrication of thin open-cell laminates in which encapsulated incendiary materials are sealed inside some of the cells and later ignited. This technique however requires complex encapsulation procedures, complex fabrication structure of the laminate and an oxygen environment to support combustion. Further this technique is directed to destruction/disfiguring of equipment adjacent the laminate rather than acting as a structural seal between different regions and would leave a partial occlusion that would restrict the flow. The present invention avoids the limitations of the prior art and provides a method for structurally sealing specific regions and removing the seal remotely and completely at a later time without requiring oxygen and without danger of degradation to nearby personnel or equipment.